Electrical circuit-controlling device



Jan. 7, 1930. w. c. ROE

ELECTRICAL cmcun' CONTROLLING DEVICE Filed June 6. 1922 2 Sheets-Sheet 1 ELECTRICAL CIRCUIT CONTROLLING DEVICE Filed June 6. 1922 2 Sheets-Sheet 2 /nven/on W////'am Roe.

Patented Jan. 7, 1930' UNITED STATES PATENT OFFICE WILLIAM ELECTRICAL CIRCUIT- Application filed June 6,

This invention relates to electrical circuit controlling devices and particularly to improvements in circuit controlling devices employed in connection with burglar alarm H systems on doors or windows.

It is an object of the invention to provide a circuit controlling device which is simple in construction, economical in cost, and which may readily be attached to any portion of a door or window.

More specifically, the invention provides an improved door or window trip adjustably supported on a mounting plate, which is adapted to be fixed to a door panel or window molding, in which position the contact element is movable toward and away from the door or window sash. The contact-making element of the device comprises a spring block which is provided with a cover containing a projecting tongue adapted to engage with an opening on either side of the block leaving a circular opening on the opposite side for the entrance of connecting wires, the block thereby fitting either side of the door or window.

Other objects and features of the invention, and the particular arrangement of parts which is thought most advantageous, will appear from a consideration of the following description taken in conjunction with the accompanying drawing and the appended claim.

In the drawing, Fig. 1 is a top view, partly in section, of a window sash and molding mounting an alarm device of the invention in its preferred form; Fig. 2 shows a front sectional view hereof; Fig. 3 is a perspective view of the preferred form of mounting plate Fig. i is a perspective view of the spring block which is adapted to be mounted thereon; Fig. 5 is a perspective view of the reversible cover therefor; Fig. 6 is an elevation, partly in section, of a contact plate adapted to cooperate with the spring block; Fig. 7 is an end sectional view of the contact plate; and Figs. 8 and 9 show the development of a coil spring employed in the spring block, the former being an elevation of the blank spring before being coiled, and the latter being a perspective view of the completed spring.

C. ROE, OF NEW YORK, N. Y., ASSIGNOR, TO HOLMES ELECTRIC PROTECTIVE COMPANY, OF NEW YORK, N. Y.,

A CORPORATION or new YORK CONTROLLING nnvron 1922. Serial No. 566,361.

Referring now to the drawing, in which like reference numerals designate similar parts throughout the several views, there is provided a mounting plate 5 of any durable material, such as sheet metal. The plate 5 is bent into a lower portion 6, which is adapted to be rigidly secured to a window molding, and an upper portion 7 which is adapted to act. as a support for the circuit-controlling window trip, as hereinafter described. The lower portion 6 of the mounting plate 5 is provided with a plurality of screw holes 8 so as to render it possible to screw the plate 5 to any desired part of the molding. The upper portion "1' is provided with a pair of elongated screw holes 9 through the medium of which the circuit-controlling block may be mounted on the plate 5 and be adjustably screwed in different positions thereon. The portion 7 of the plate 5 is also provided with a circular hole 10 through which the alarm conductors may be led to complete the circuit connections. A punched portion 11 on the plate 5 extends to the level of the portion 6 and contains slots 12 for the insertion of screws or nails which hold it in place on the window molding. By referring particularly to Fig. 1, it will be seen that the mounting plate 5 will span any door panel or Window molding no matter how many projecting parts may be included therein and may be readily iiXed in place on such a panel or molding by means of screws acting in holes 8 and 12. v v

The contact-containing element itself consists of a block 13 of insulating material having a projecting knuckle 14 which is normally tensioned outwardly bymeans of a coil spring 15. This circuit controlling device is specially adapted for use in alarm systems of a well-known type, which have been used for a number of years, in which the alarm devices of the system are actuated by a break or shortcircuit inthe wiring of the system, of which the contact block 13 is a part. This alarm circuit is established through a metallic con tact plate 17 adapted to rest upon the door or window sash, the knuckle 14, and the coil spring 15. When the spring block 13 is restingin operative position on the side molding 2 rmasve the pressure on the projecting knuckle 14 compresses the coil spring 15, and carries the knuckle out of engagement with a leaf contact 16. When the door or window is opened, the knuckle 1% slides off the contact plate 17, thus breaking the normal alarm circuit, and the knuckle is pressed forward by the spring 15 to engage the leaf contact 16, thus establishing a short-circuit, whichinsures the sounding of an alarm. As shown in Figs. 8 and 9, the spring 15 is blanked out of a single strip of metal which is then coiled upon itself. By forming the spring in this manner, it is possible to obtain a compact and powerful spring which will exert a maximum tension upon the knuckle 14 while acting through a very limited range.

In order that the spring block 13 may be made adjustable to both right and left sides of a door or window, a cover 18 is provided therefor, which has a projecting portion 19 on one side, which adapted to fit into a'corresponding slot 20 on either side of the block. The other side of the cover 18 is provided with a semi-circular grooved projection 21. When the cover is in place on the block 13 the projection 1S) completely fills one of the slots 20, while the projection 21 only partially fills the other slot, leaving a hole for the entrance of connecting wires on that side. The cover 18 is held in the desired position on the'block 13 by means of suitable screws 22. vVhen assembled, this spring block is adapted to be mounted by means of screws 23, which engage nuts or strips 24 on the opposite side of the mounting plate 5. A second screw 25 may also be provide d in the strip 24 to limit the movement of the screw 23in the elongated screw hole 9. Since the contact block 13 is supported by the screws 23, it will be obvious that the movement of this block upon the mounting plate 5 is limited in both directions depending upon the position of the screws 23 and 25. It will also be seen that when the mounting plate 5 is fixed to a window molding, as shown in Figs. 1 and 2, the adjustable block 13 is adapted to be moved to and from the window sash to accommodate itself to any size molding, so that tle knuckle 14; will engage the contact plate 1 The unitary contact plate 17, best shown in Figs. 6 and 7, consists of a single metal strip 26, the edges of which are bent over to enfold and tightly clamp a strip of insulating material 27. The metal strip 26 is provided with two large screw holes 28, and the insulating strip 27 is provided with two correspondingly spaced smaller screw holes 29. WVhen the contact plate 17 is placed upon a door or window molding a second insulating strip 30 is placed intermediate the metal strip 26 and the door or window molding. Both the contact strip 17 and the insulating strip 30 are then secured to the molding by means of sultable screws 31, which pass through screw holes 28 and 29, engaging the latter, but not the former screw holes. It will thus be seen that even if the contact strip 17 is mounted upon a metal door or window frame, still no metal, not even the screws 31, touches the metal contact strip 26.

It will be obvious that certain departures may be made from the specific construction herein shown and described, and it is, therefore, not intended to limit the invention, except within the scope of the appended claim.

hat is claimed is A circuit controlling device for burglar alarm systems comprising an apertured block of insulating material, openings on each side of said block extending into said aperture, a cover having a projecting ear which registers with and closes either of said openings, arranged to be reversibly titted over said aperture, a contact arm pivot-ally mounted on said block in said aperture and adapted to project beyond the face of said block, a selfsupporting coiled spring in said aperture held under tension and bearing against said arm, and a contact spring in said aperture for making contact with said arm when it is in a projected position and out of contact when it is in a depressed position.

In witness whereof, I hereunto subscribe my name this 31st day of May A. D., 1922.

WILLIAM C. ROE. 

